Dependencies/libvorbis/lib/res0.c

   1 /********************************************************************
   2  *                                                                  *
   3  * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE.   *
   4  * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS     *
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   6  * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING.       *
   7  *                                                                  *
   8  * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2010             *
   9  * by the Xiph.Org Foundation http://www.xiph.org/                  *
  10  *                                                                  *
  11  ********************************************************************
  12
  13  function: residue backend 0, 1 and 2 implementation
  14  last mod: $Id: res0.c 16962 2010-03-11 07:30:34Z xiphmont $
  15
  16  ********************************************************************/
  17
  18 /* Slow, slow, slow, simpleminded and did I mention it was slow?  The
  19    encode/decode loops are coded for clarity and performance is not
  20    yet even a nagging little idea lurking in the shadows.  Oh and BTW,
  21    it's slow. */
  22
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <math.h>
  26 #include <ogg/ogg.h>
  27 #include "vorbis/codec.h"
  28 #include "codec_internal.h"
  29 #include "registry.h"
  30 #include "codebook.h"
  31 #include "misc.h"
  32 #include "os.h"
  33
  34 //#define TRAIN_RES 1
  35 //#define TRAIN_RESAUX 1
  36
  37 #if defined(TRAIN_RES) || defined (TRAIN_RESAUX)
  38 #include <stdio.h>
  39 #endif
  40
  41 typedef struct {
  42   vorbis_info_residue0 *info;
  43
  44   int         parts;
  45   int         stages;
  46   codebook   *fullbooks;
  47   codebook   *phrasebook;
  48   codebook ***partbooks;
  49
  50   int         partvals;
  51   int       **decodemap;
  52
  53   long      postbits;
  54   long      phrasebits;
  55   long      frames;
  56
  57 #if defined(TRAIN_RES) || defined(TRAIN_RESAUX)
  58   int        train_seq;
  59   long      *training_data[8][64];
  60   float      training_max[8][64];
  61   float      training_min[8][64];
  62   float     tmin;
  63   float     tmax;
  64   int       submap;
  65 #endif
  66
  67 } vorbis_look_residue0;
  68
  69 void res0_free_info(vorbis_info_residue *i){
  70   vorbis_info_residue0 *info=(vorbis_info_residue0 *)i;
  71   if(info){
  72     memset(info,0,sizeof(*info));
  73     _ogg_free(info);
  74   }
  75 }
  76
  77 void res0_free_look(vorbis_look_residue *i){
  78   int j;
  79   if(i){
  80
  81     vorbis_look_residue0 *look=(vorbis_look_residue0 *)i;
  82
  83 #ifdef TRAIN_RES
  84     {
  85       int j,k,l;
  86       for(j=0;j<look->parts;j++){
  87         /*fprintf(stderr,"partition %d: ",j);*/
  88         for(k=0;k<8;k++)
  89           if(look->training_data[k][j]){
  90             char buffer[80];
  91             FILE *of;
  92             codebook *statebook=look->partbooks[j][k];
  93
  94             /* long and short into the same bucket by current convention */
  95             sprintf(buffer,"res_sub%d_part%d_pass%d.vqd",look->submap,j,k);
  96             of=fopen(buffer,"a");
  97
  98             for(l=0;l<statebook->entries;l++)
  99               fprintf(of,"%d:%ld\n",l,look->training_data[k][j][l]);
 100
 101             fclose(of);
 102
 103             /*fprintf(stderr,"%d(%.2f|%.2f) ",k,
 104               look->training_min[k][j],look->training_max[k][j]);*/
 105
 106             _ogg_free(look->training_data[k][j]);
 107             look->training_data[k][j]=NULL;
 108           }
 109         /*fprintf(stderr,"\n");*/
 110       }
 111     }
 112     fprintf(stderr,"min/max residue: %g::%g\n",look->tmin,look->tmax);
 113
 114     /*fprintf(stderr,"residue bit usage %f:%f (%f total)\n",
 115             (float)look->phrasebits/look->frames,
 116             (float)look->postbits/look->frames,
 117             (float)(look->postbits+look->phrasebits)/look->frames);*/
 118 #endif
 119
 120
 121     /*vorbis_info_residue0 *info=look->info;
 122
 123     fprintf(stderr,
 124             "%ld frames encoded in %ld phrasebits and %ld residue bits "
 125             "(%g/frame) \n",look->frames,look->phrasebits,
 126             look->resbitsflat,
 127             (look->phrasebits+look->resbitsflat)/(float)look->frames);
 128
 129     for(j=0;j<look->parts;j++){
 130       long acc=0;
 131       fprintf(stderr,"\t[%d] == ",j);
 132       for(k=0;k<look->stages;k++)
 133         if((info->secondstages[j]>>k)&1){
 134           fprintf(stderr,"%ld,",look->resbits[j][k]);
 135           acc+=look->resbits[j][k];
 136         }
 137
 138       fprintf(stderr,":: (%ld vals) %1.2fbits/sample\n",look->resvals[j],
 139               acc?(float)acc/(look->resvals[j]*info->grouping):0);
 140     }
 141     fprintf(stderr,"\n");*/
 142
 143     for(j=0;j<look->parts;j++)
 144       if(look->partbooks[j])_ogg_free(look->partbooks[j]);
 145     _ogg_free(look->partbooks);
 146     for(j=0;j<look->partvals;j++)
 147       _ogg_free(look->decodemap[j]);
 148     _ogg_free(look->decodemap);
 149
 150     memset(look,0,sizeof(*look));
 151     _ogg_free(look);
 152   }
 153 }
 154
 155 static int ilog(unsigned int v){
 156   int ret=0;
 157   while(v){
 158     ret++;
 159     v>>=1;
 160   }
 161   return(ret);
 162 }
 163
 164 static int icount(unsigned int v){
 165   int ret=0;
 166   while(v){
 167     ret+=v&1;
 168     v>>=1;
 169   }
 170   return(ret);
 171 }
 172
 173
 174 void res0_pack(vorbis_info_residue *vr,oggpack_buffer *opb){
 175   vorbis_info_residue0 *info=(vorbis_info_residue0 *)vr;
 176   int j,acc=0;
 177   oggpack_write(opb,info->begin,24);
 178   oggpack_write(opb,info->end,24);
 179
 180   oggpack_write(opb,info->grouping-1,24);  /* residue vectors to group and
 181                                              code with a partitioned book */
 182   oggpack_write(opb,info->partitions-1,6); /* possible partition choices */
 183   oggpack_write(opb,info->groupbook,8);  /* group huffman book */
 184
 185   /* secondstages is a bitmask; as encoding progresses pass by pass, a
 186      bitmask of one indicates this partition class has bits to write
 187      this pass */
 188   for(j=0;j<info->partitions;j++){
 189     if(ilog(info->secondstages[j])>3){
 190       /* yes, this is a minor hack due to not thinking ahead */
 191       oggpack_write(opb,info->secondstages[j],3);
 192       oggpack_write(opb,1,1);
 193       oggpack_write(opb,info->secondstages[j]>>3,5);
 194     }else
 195       oggpack_write(opb,info->secondstages[j],4); /* trailing zero */
 196     acc+=icount(info->secondstages[j]);
 197   }
 198   for(j=0;j<acc;j++)
 199     oggpack_write(opb,info->booklist[j],8);
 200
 201 }
 202
 203 /* vorbis_info is for range checking */
 204 vorbis_info_residue *res0_unpack(vorbis_info *vi,oggpack_buffer *opb){
 205   int j,acc=0;
 206   vorbis_info_residue0 *info=_ogg_calloc(1,sizeof(*info));
 207   codec_setup_info     *ci=vi->codec_setup;
 208
 209   info->begin=oggpack_read(opb,24);
 210   info->end=oggpack_read(opb,24);
 211   info->grouping=oggpack_read(opb,24)+1;
 212   info->partitions=oggpack_read(opb,6)+1;
 213   info->groupbook=oggpack_read(opb,8);
 214
 215   /* check for premature EOP */
 216   if(info->groupbook<0)goto errout;
 217
 218   for(j=0;j<info->partitions;j++){
 219     int cascade=oggpack_read(opb,3);
 220     int cflag=oggpack_read(opb,1);
 221     if(cflag<0) goto errout;
 222     if(cflag){
 223       int c=oggpack_read(opb,5);
 224       if(c<0) goto errout;
 225       cascade|=(c<<3);
 226     }
 227     info->secondstages[j]=cascade;
 228
 229     acc+=icount(cascade);
 230   }
 231   for(j=0;j<acc;j++){
 232     int book=oggpack_read(opb,8);
 233     if(book<0) goto errout;
 234     info->booklist[j]=book;
 235   }
 236
 237   if(info->groupbook>=ci->books)goto errout;
 238   for(j=0;j<acc;j++){
 239     if(info->booklist[j]>=ci->books)goto errout;
 240     if(ci->book_param[info->booklist[j]]->maptype==0)goto errout;
 241   }
 242
 243   /* verify the phrasebook is not specifying an impossible or
 244      inconsistent partitioning scheme. */
 245   /* modify the phrasebook ranging check from r16327; an early beta
 246      encoder had a bug where it used an oversized phrasebook by
 247      accident.  These files should continue to be playable, but don't
 248      allow an exploit */
 249   {
 250     int entries = ci->book_param[info->groupbook]->entries;
 251     int dim = ci->book_param[info->groupbook]->dim;
 252     int partvals = 1;
 253     while(dim>0){
 254       partvals *= info->partitions;
 255       if(partvals > entries) goto errout;
 256       dim--;
 257     }
 258     info->partvals = partvals;
 259   }
 260
 261   return(info);
 262  errout:
 263   res0_free_info(info);
 264   return(NULL);
 265 }
 266
 267 vorbis_look_residue *res0_look(vorbis_dsp_state *vd,
 268                                vorbis_info_residue *vr){
 269   vorbis_info_residue0 *info=(vorbis_info_residue0 *)vr;
 270   vorbis_look_residue0 *look=_ogg_calloc(1,sizeof(*look));
 271   codec_setup_info     *ci=vd->vi->codec_setup;
 272
 273   int j,k,acc=0;
 274   int dim;
 275   int maxstage=0;
 276   look->info=info;
 277
 278   look->parts=info->partitions;
 279   look->fullbooks=ci->fullbooks;
 280   look->phrasebook=ci->fullbooks+info->groupbook;
 281   dim=look->phrasebook->dim;
 282
 283   look->partbooks=_ogg_calloc(look->parts,sizeof(*look->partbooks));
 284
 285   for(j=0;j<look->parts;j++){
 286     int stages=ilog(info->secondstages[j]);
 287     if(stages){
 288       if(stages>maxstage)maxstage=stages;
 289       look->partbooks[j]=_ogg_calloc(stages,sizeof(*look->partbooks[j]));
 290       for(k=0;k<stages;k++)
 291         if(info->secondstages[j]&(1<<k)){
 292           look->partbooks[j][k]=ci->fullbooks+info->booklist[acc++];
 293 #ifdef TRAIN_RES
 294           look->training_data[k][j]=_ogg_calloc(look->partbooks[j][k]->entries,
 295                                            sizeof(***look->training_data));
 296 #endif
 297         }
 298     }
 299   }
 300
 301   look->partvals=1;
 302   for(j=0;j<dim;j++)
 303       look->partvals*=look->parts;
 304
 305   look->stages=maxstage;
 306   look->decodemap=_ogg_malloc(look->partvals*sizeof(*look->decodemap));
 307   for(j=0;j<look->partvals;j++){
 308     long val=j;
 309     long mult=look->partvals/look->parts;
 310     look->decodemap[j]=_ogg_malloc(dim*sizeof(*look->decodemap[j]));
 311     for(k=0;k<dim;k++){
 312       long deco=val/mult;
 313       val-=deco*mult;
 314       mult/=look->parts;
 315       look->decodemap[j][k]=deco;
 316     }
 317   }
 318 #if defined(TRAIN_RES) || defined (TRAIN_RESAUX)
 319   {
 320     static int train_seq=0;
 321     look->train_seq=train_seq++;
 322   }
 323 #endif
 324   return(look);
 325 }
 326
 327 /* break an abstraction and copy some code for performance purposes */
 328 static int local_book_besterror(codebook *book,int *a){
 329   int dim=book->dim;
 330   int i,j,o;
 331   int minval=book->minval;
 332   int del=book->delta;
 333   int qv=book->quantvals;
 334   int ze=(qv>>1);
 335   int index=0;
 336   /* assumes integer/centered encoder codebook maptype 1 no more than dim 8 */
 337   int p[8]={0,0,0,0,0,0,0,0};
 338
 339   if(del!=1){
 340     for(i=0,o=dim;i<dim;i++){
 341       int v = (a[--o]-minval+(del>>1))/del;
 342       int m = (v<ze ? ((ze-v)<<1)-1 : ((v-ze)<<1));
 343       index = index*qv+ (m<0?0:(m>=qv?qv-1:m));
 344       p[o]=v*del+minval;
 345     }
 346   }else{
 347     for(i=0,o=dim;i<dim;i++){
 348       int v = a[--o]-minval;
 349       int m = (v<ze ? ((ze-v)<<1)-1 : ((v-ze)<<1));
 350       index = index*qv+ (m<0?0:(m>=qv?qv-1:m));
 351       p[o]=v*del+minval;
 352     }
 353   }
 354
 355   if(book->c->lengthlist[index]<=0){
 356     const static_codebook *c=book->c;
 357     int best=-1;
 358     /* assumes integer/centered encoder codebook maptype 1 no more than dim 8 */
 359     int e[8]={0,0,0,0,0,0,0,0};
 360     int maxval = book->minval + book->delta*(book->quantvals-1);
 361     for(i=0;i<book->entries;i++){
 362       if(c->lengthlist[i]>0){
 363         int this=0;
 364         for(j=0;j<dim;j++){
 365           int val=(e[j]-a[j]);
 366           this+=val*val;
 367         }
 368         if(best==-1 || this<best){
 369           memcpy(p,e,sizeof(p));
 370           best=this;
 371           index=i;
 372         }
 373       }
 374       /* assumes the value patterning created by the tools in vq/ */
 375       j=0;
 376       while(e[j]>=maxval)
 377         e[j++]=0;
 378       if(e[j]>=0)
 379         e[j]+=book->delta;
 380       e[j]= -e[j];
 381     }
 382   }
 383
 384   if(index>-1){
 385     for(i=0;i<dim;i++)
 386       *a++ -= p[i];
 387   }
 388
 389   return(index);
 390 }
 391
 392 static int _encodepart(oggpack_buffer *opb,int *vec, int n,
 393                        codebook *book,long *acc){
 394   int i,bits=0;
 395   int dim=book->dim;
 396   int step=n/dim;
 397
 398   for(i=0;i<step;i++){
 399     int entry=local_book_besterror(book,vec+i*dim);
 400
 401 #ifdef TRAIN_RES
 402     if(entry>=0)
 403       acc[entry]++;
 404 #endif
 405
 406     bits+=vorbis_book_encode(book,entry,opb);
 407
 408   }
 409
 410   return(bits);
 411 }
 412
 413 static long **_01class(vorbis_block *vb,vorbis_look_residue *vl,
 414                        int **in,int ch){
 415   long i,j,k;
 416   vorbis_look_residue0 *look=(vorbis_look_residue0 *)vl;
 417   vorbis_info_residue0 *info=look->info;
 418
 419   /* move all this setup out later */
 420   int samples_per_partition=info->grouping;
 421   int possible_partitions=info->partitions;
 422   int n=info->end-info->begin;
 423
 424   int partvals=n/samples_per_partition;
 425   long **partword=_vorbis_block_alloc(vb,ch*sizeof(*partword));
 426   float scale=100./samples_per_partition;
 427
 428   /* we find the partition type for each partition of each
 429      channel.  We'll go back and do the interleaved encoding in a
 430      bit.  For now, clarity */
 431
 432   for(i=0;i<ch;i++){
 433     partword[i]=_vorbis_block_alloc(vb,n/samples_per_partition*sizeof(*partword[i]));
 434     memset(partword[i],0,n/samples_per_partition*sizeof(*partword[i]));
 435   }
 436
 437   for(i=0;i<partvals;i++){
 438     int offset=i*samples_per_partition+info->begin;
 439     for(j=0;j<ch;j++){
 440       int max=0;
 441       int ent=0;
 442       for(k=0;k<samples_per_partition;k++){
 443         if(abs(in[j][offset+k])>max)max=abs(in[j][offset+k]);
 444         ent+=abs(in[j][offset+k]);
 445       }
 446       ent*=scale;
 447
 448       for(k=0;k<possible_partitions-1;k++)
 449         if(max<=info->classmetric1[k] &&
 450            (info->classmetric2[k]<0 || ent<info->classmetric2[k]))
 451           break;
 452
 453       partword[j][i]=k;
 454     }
 455   }
 456
 457 #ifdef TRAIN_RESAUX
 458   {
 459     FILE *of;
 460     char buffer[80];
 461
 462     for(i=0;i<ch;i++){
 463       sprintf(buffer,"resaux_%d.vqd",look->train_seq);
 464       of=fopen(buffer,"a");
 465       for(j=0;j<partvals;j++)
 466         fprintf(of,"%ld, ",partword[i][j]);
 467       fprintf(of,"\n");
 468       fclose(of);
 469     }
 470   }
 471 #endif
 472   look->frames++;
 473
 474   return(partword);
 475 }
 476
 477 /* designed for stereo or other modes where the partition size is an
 478    integer multiple of the number of channels encoded in the current
 479    submap */
 480 static long **_2class(vorbis_block *vb,vorbis_look_residue *vl,int **in,
 481                       int ch){
 482   long i,j,k,l;
 483   vorbis_look_residue0 *look=(vorbis_look_residue0 *)vl;
 484   vorbis_info_residue0 *info=look->info;
 485
 486   /* move all this setup out later */
 487   int samples_per_partition=info->grouping;
 488   int possible_partitions=info->partitions;
 489   int n=info->end-info->begin;
 490
 491   int partvals=n/samples_per_partition;
 492   long **partword=_vorbis_block_alloc(vb,sizeof(*partword));
 493
 494 #if defined(TRAIN_RES) || defined (TRAIN_RESAUX)
 495   FILE *of;
 496   char buffer[80];
 497 #endif
 498
 499   partword[0]=_vorbis_block_alloc(vb,partvals*sizeof(*partword[0]));
 500   memset(partword[0],0,partvals*sizeof(*partword[0]));
 501
 502   for(i=0,l=info->begin/ch;i<partvals;i++){
 503     int magmax=0;
 504     int angmax=0;
 505     for(j=0;j<samples_per_partition;j+=ch){
 506       if(abs(in[0][l])>magmax)magmax=abs(in[0][l]);
 507       for(k=1;k<ch;k++)
 508         if(abs(in[k][l])>angmax)angmax=abs(in[k][l]);
 509       l++;
 510     }
 511
 512     for(j=0;j<possible_partitions-1;j++)
 513       if(magmax<=info->classmetric1[j] &&
 514          angmax<=info->classmetric2[j])
 515         break;
 516
 517     partword[0][i]=j;
 518
 519   }
 520
 521 #ifdef TRAIN_RESAUX
 522   sprintf(buffer,"resaux_%d.vqd",look->train_seq);
 523   of=fopen(buffer,"a");
 524   for(i=0;i<partvals;i++)
 525     fprintf(of,"%ld, ",partword[0][i]);
 526   fprintf(of,"\n");
 527   fclose(of);
 528 #endif
 529
 530   look->frames++;
 531
 532   return(partword);
 533 }
 534
 535 static int _01forward(oggpack_buffer *opb,
 536                       vorbis_block *vb,vorbis_look_residue *vl,
 537                       int **in,int ch,
 538                       long **partword,
 539                       int (*encode)(oggpack_buffer *,int *,int,
 540                                     codebook *,long *),
 541                       int submap){
 542   long i,j,k,s;
 543   vorbis_look_residue0 *look=(vorbis_look_residue0 *)vl;
 544   vorbis_info_residue0 *info=look->info;
 545
 546 #ifdef TRAIN_RES
 547   look->submap=submap;
 548 #endif
 549
 550   /* move all this setup out later */
 551   int samples_per_partition=info->grouping;
 552   int possible_partitions=info->partitions;
 553   int partitions_per_word=look->phrasebook->dim;
 554   int n=info->end-info->begin;
 555
 556   int partvals=n/samples_per_partition;
 557   long resbits[128];
 558   long resvals[128];
 559
 560 #ifdef TRAIN_RES
 561   for(i=0;i<ch;i++)
 562     for(j=info->begin;j<info->end;j++){
 563       if(in[i][j]>look->tmax)look->tmax=in[i][j];
 564       if(in[i][j]<look->tmin)look->tmin=in[i][j];
 565     }
 566 #endif
 567
 568   memset(resbits,0,sizeof(resbits));
 569   memset(resvals,0,sizeof(resvals));
 570
 571   /* we code the partition words for each channel, then the residual
 572      words for a partition per channel until we've written all the
 573      residual words for that partition word.  Then write the next
 574      partition channel words... */
 575
 576   for(s=0;s<look->stages;s++){
 577
 578     for(i=0;i<partvals;){
 579
 580       /* first we encode a partition codeword for each channel */
 581       if(s==0){
 582         for(j=0;j<ch;j++){
 583           long val=partword[j][i];
 584           for(k=1;k<partitions_per_word;k++){
 585             val*=possible_partitions;
 586             if(i+k<partvals)
 587               val+=partword[j][i+k];
 588           }
 589
 590           /* training hack */
 591           if(val<look->phrasebook->entries)
 592             look->phrasebits+=vorbis_book_encode(look->phrasebook,val,opb);
 593 #if 0 /*def TRAIN_RES*/
 594           else
 595             fprintf(stderr,"!");
 596 #endif
 597
 598         }
 599       }
 600
 601       /* now we encode interleaved residual values for the partitions */
 602       for(k=0;k<partitions_per_word && i<partvals;k++,i++){
 603         long offset=i*samples_per_partition+info->begin;
 604
 605         for(j=0;j<ch;j++){
 606           if(s==0)resvals[partword[j][i]]+=samples_per_partition;
 607           if(info->secondstages[partword[j][i]]&(1<<s)){
 608             codebook *statebook=look->partbooks[partword[j][i]][s];
 609             if(statebook){
 610               int ret;
 611               long *accumulator=NULL;
 612
 613 #ifdef TRAIN_RES
 614               accumulator=look->training_data[s][partword[j][i]];
 615               {
 616                 int l;
 617                 int *samples=in[j]+offset;
 618                 for(l=0;l<samples_per_partition;l++){
 619                   if(samples[l]<look->training_min[s][partword[j][i]])
 620                     look->training_min[s][partword[j][i]]=samples[l];
 621                   if(samples[l]>look->training_max[s][partword[j][i]])
 622                     look->training_max[s][partword[j][i]]=samples[l];
 623                 }
 624               }
 625 #endif
 626
 627               ret=encode(opb,in[j]+offset,samples_per_partition,
 628                          statebook,accumulator);
 629
 630               look->postbits+=ret;
 631               resbits[partword[j][i]]+=ret;
 632             }
 633           }
 634         }
 635       }
 636     }
 637   }
 638
 639   /*{
 640     long total=0;
 641     long totalbits=0;
 642     fprintf(stderr,"%d :: ",vb->mode);
 643     for(k=0;k<possible_partitions;k++){
 644     fprintf(stderr,"%ld/%1.2g, ",resvals[k],(float)resbits[k]/resvals[k]);
 645     total+=resvals[k];
 646     totalbits+=resbits[k];
 647     }
 648
 649     fprintf(stderr,":: %ld:%1.2g\n",total,(double)totalbits/total);
 650     }*/
 651
 652   return(0);
 653 }
 654
 655 /* a truncated packet here just means 'stop working'; it's not an error */
 656 static int _01inverse(vorbis_block *vb,vorbis_look_residue *vl,
 657                       float **in,int ch,
 658                       long (*decodepart)(codebook *, float *,
 659                                          oggpack_buffer *,int)){
 660
 661   long i,j,k,l,s;
 662   vorbis_look_residue0 *look=(vorbis_look_residue0 *)vl;
 663   vorbis_info_residue0 *info=look->info;
 664
 665   /* move all this setup out later */
 666   int samples_per_partition=info->grouping;
 667   int partitions_per_word=look->phrasebook->dim;
 668   int max=vb->pcmend>>1;
 669   int end=(info->end<max?info->end:max);
 670   int n=end-info->begin;
 671
 672   if(n>0){
 673     int partvals=n/samples_per_partition;
 674     int partwords=(partvals+partitions_per_word-1)/partitions_per_word;
 675     int ***partword=alloca(ch*sizeof(*partword));
 676
 677     for(j=0;j<ch;j++)
 678       partword[j]=_vorbis_block_alloc(vb,partwords*sizeof(*partword[j]));
 679
 680     for(s=0;s<look->stages;s++){
 681
 682       /* each loop decodes on partition codeword containing
 683          partitions_per_word partitions */
 684       for(i=0,l=0;i<partvals;l++){
 685         if(s==0){
 686           /* fetch the partition word for each channel */
 687           for(j=0;j<ch;j++){
 688             int temp=vorbis_book_decode(look->phrasebook,&vb->opb);
 689
 690             if(temp==-1 || temp>=info->partvals)goto eopbreak;
 691             partword[j][l]=look->decodemap[temp];
 692             if(partword[j][l]==NULL)goto errout;
 693           }
 694         }
 695
 696         /* now we decode residual values for the partitions */
 697         for(k=0;k<partitions_per_word && i<partvals;k++,i++)
 698           for(j=0;j<ch;j++){
 699             long offset=info->begin+i*samples_per_partition;
 700             if(info->secondstages[partword[j][l][k]]&(1<<s)){
 701               codebook *stagebook=look->partbooks[partword[j][l][k]][s];
 702               if(stagebook){
 703                 if(decodepart(stagebook,in[j]+offset,&vb->opb,
 704                               samples_per_partition)==-1)goto eopbreak;
 705               }
 706             }
 707           }
 708       }
 709     }
 710   }
 711  errout:
 712  eopbreak:
 713   return(0);
 714 }
 715
 716 int res0_inverse(vorbis_block *vb,vorbis_look_residue *vl,
 717                  float **in,int *nonzero,int ch){
 718   int i,used=0;
 719   for(i=0;i<ch;i++)
 720     if(nonzero[i])
 721       in[used++]=in[i];
 722   if(used)
 723     return(_01inverse(vb,vl,in,used,vorbis_book_decodevs_add));
 724   else
 725     return(0);
 726 }
 727
 728 int res1_forward(oggpack_buffer *opb,vorbis_block *vb,vorbis_look_residue *vl,
 729                  int **in,int *nonzero,int ch, long **partword, int submap){
 730   int i,used=0;
 731   for(i=0;i<ch;i++)
 732     if(nonzero[i])
 733       in[used++]=in[i];
 734
 735   if(used){
 736     return _01forward(opb,vb,vl,in,used,partword,_encodepart,submap);
 737   }else{
 738     return(0);
 739   }
 740 }
 741
 742 long **res1_class(vorbis_block *vb,vorbis_look_residue *vl,
 743                   int **in,int *nonzero,int ch){
 744   int i,used=0;
 745   for(i=0;i<ch;i++)
 746     if(nonzero[i])
 747       in[used++]=in[i];
 748   if(used)
 749     return(_01class(vb,vl,in,used));
 750   else
 751     return(0);
 752 }
 753
 754 int res1_inverse(vorbis_block *vb,vorbis_look_residue *vl,
 755                  float **in,int *nonzero,int ch){
 756   int i,used=0;
 757   for(i=0;i<ch;i++)
 758     if(nonzero[i])
 759       in[used++]=in[i];
 760   if(used)
 761     return(_01inverse(vb,vl,in,used,vorbis_book_decodev_add));
 762   else
 763     return(0);
 764 }
 765
 766 long **res2_class(vorbis_block *vb,vorbis_look_residue *vl,
 767                   int **in,int *nonzero,int ch){
 768   int i,used=0;
 769   for(i=0;i<ch;i++)
 770     if(nonzero[i])used++;
 771   if(used)
 772     return(_2class(vb,vl,in,ch));
 773   else
 774     return(0);
 775 }
 776
 777 /* res2 is slightly more different; all the channels are interleaved
 778    into a single vector and encoded. */
 779
 780 int res2_forward(oggpack_buffer *opb,
 781                  vorbis_block *vb,vorbis_look_residue *vl,
 782                  int **in,int *nonzero,int ch, long **partword,int submap){
 783   long i,j,k,n=vb->pcmend/2,used=0;
 784
 785   /* don't duplicate the code; use a working vector hack for now and
 786      reshape ourselves into a single channel res1 */
 787   /* ugly; reallocs for each coupling pass :-( */
 788   int *work=_vorbis_block_alloc(vb,ch*n*sizeof(*work));
 789   for(i=0;i<ch;i++){
 790     int *pcm=in[i];
 791     if(nonzero[i])used++;
 792     for(j=0,k=i;j<n;j++,k+=ch)
 793       work[k]=pcm[j];
 794   }
 795
 796   if(used){
 797     return _01forward(opb,vb,vl,&work,1,partword,_encodepart,submap);
 798   }else{
 799     return(0);
 800   }
 801 }
 802
 803 /* duplicate code here as speed is somewhat more important */
 804 int res2_inverse(vorbis_block *vb,vorbis_look_residue *vl,
 805                  float **in,int *nonzero,int ch){
 806   long i,k,l,s;
 807   vorbis_look_residue0 *look=(vorbis_look_residue0 *)vl;
 808   vorbis_info_residue0 *info=look->info;
 809
 810   /* move all this setup out later */
 811   int samples_per_partition=info->grouping;
 812   int partitions_per_word=look->phrasebook->dim;
 813   int max=(vb->pcmend*ch)>>1;
 814   int end=(info->end<max?info->end:max);
 815   int n=end-info->begin;
 816
 817   if(n>0){
 818     int partvals=n/samples_per_partition;
 819     int partwords=(partvals+partitions_per_word-1)/partitions_per_word;
 820     int **partword=_vorbis_block_alloc(vb,partwords*sizeof(*partword));
 821
 822     for(i=0;i<ch;i++)if(nonzero[i])break;
 823     if(i==ch)return(0); /* no nonzero vectors */
 824
 825     for(s=0;s<look->stages;s++){
 826       for(i=0,l=0;i<partvals;l++){
 827
 828         if(s==0){
 829           /* fetch the partition word */
 830           int temp=vorbis_book_decode(look->phrasebook,&vb->opb);
 831           if(temp==-1 || temp>info->partvals)goto eopbreak;
 832           partword[l]=look->decodemap[temp];
 833           if(partword[l]==NULL)goto errout;
 834         }
 835
 836         /* now we decode residual values for the partitions */
 837         for(k=0;k<partitions_per_word && i<partvals;k++,i++)
 838           if(info->secondstages[partword[l][k]]&(1<<s)){
 839             codebook *stagebook=look->partbooks[partword[l][k]][s];
 840
 841             if(stagebook){
 842               if(vorbis_book_decodevv_add(stagebook,in,
 843                                           i*samples_per_partition+info->begin,ch,
 844                                           &vb->opb,samples_per_partition)==-1)
 845                 goto eopbreak;
 846             }
 847           }
 848       }
 849     }
 850   }
 851  errout:
 852  eopbreak:
 853   return(0);
 854 }
 855
 856
 857 const vorbis_func_residue residue0_exportbundle={
 858   NULL,
 859   &res0_unpack,
 860   &res0_look,
 861   &res0_free_info,
 862   &res0_free_look,
 863   NULL,
 864   NULL,
 865   &res0_inverse
 866 };
 867
 868 const vorbis_func_residue residue1_exportbundle={
 869   &res0_pack,
 870   &res0_unpack,
 871   &res0_look,
 872   &res0_free_info,
 873   &res0_free_look,
 874   &res1_class,
 875   &res1_forward,
 876   &res1_inverse
 877 };
 878
 879 const vorbis_func_residue residue2_exportbundle={
 880   &res0_pack,
 881   &res0_unpack,
 882   &res0_look,
 883   &res0_free_info,
 884   &res0_free_look,
 885   &res2_class,
 886   &res2_forward,
 887   &res2_inverse
 888 };